commit-graph: avoid repeated mixed generation number warnings

When validating that a commit-graph has either all zero, or all non-zero
generation numbers, we emit a warning on both the rising and falling
edge of transitioning between the two.

So if we are unfortunate enough to see a commit-graph which has a
repeating sequence of zero, then non-zero generation numbers, we'll
generate many warnings that contain more or less the same information.

Avoid this by keeping track of a single example for a commit with zero-
and non-zero generation, and emit a single warning at the end of
verification if both are non-NULL.

Co-authored-by: Jeff King <peff@peff.net>
Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Taylor Blau <me@ttaylorr.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

1 files changed, 2 insertions, 2 deletions

diff --git a/t/t5318-commit-graph.sh b/t/t5318-commit-graph.sh
index 8e96471b34..ba65f17dd9 100755
--- a/t/t5318-commit-graph.sh
+++ b/t/t5318-commit-graph.sh
@@ -620,12 +620,12 @@ test_expect_success 'detect incorrect chunk count' '
 
 test_expect_success 'detect mixed generation numbers (non-zero to zero)' '
 	corrupt_graph_and_verify $GRAPH_BYTE_COMMIT_GENERATION_LAST "\0\0\0\0" \
-		"but non-zero elsewhere"
+		"both zero and non-zero generations"
 '
 
 test_expect_success 'detect mixed generation numbers (zero to non-zero)' '
 	corrupt_graph_and_verify $GRAPH_BYTE_COMMIT_GENERATION "\0\0\0\0" \
-		"but zero elsewhere"
+		"both zero and non-zero generations"
 '
 
 test_expect_success 'git fsck (checks commit-graph when config set to true)' '